1. Field of Invention
The present invention relates to WAN (Wireless Access Network) module based remote wakeup technology, and in particular to a WAN module based remote wakeup system and a terminal there of.
2. Description of Prior Art
The incessant development of GPRS (General Packet Radio Service), CDMA (Code Division Multiple Access), 3G (3rd Generation) technologies enables more convenient connection between a mobile terminal (e.g. a notebook computer) and the Internet. By inserting a communication card, i.e. WAN module, such as GPRS, CDMA or 3G wireless Network Interface Card (NIC) in an interface, such as USB, Cardbus or MiniPCIE) of a notebook computer, the mobile Internet log-on can be achieved while SMS (Short Messaging Service), phone call and the like can be performed on the notebook computer.
Therefore, WAN module has gradually come into the standard configuration of a notebook computer. A series of applications for remote wakeup and startup of a notebook computer via a mobile phone or another notebook computer have emerged these days. There are various methods of remotely waking up and starting a notebook computer by means of WAN module, and the basic idea is to detect the fluctuation in the operating current of WAN module.
Unfortunately, such detection solution has poor accuracy and stability. The major reason lies in that WAN module itself searches base stations periodically during its sleep status, and its operating current increases at the time of searching base stations, which may incur a malfunction of a WAN module based remote wakeup terminal. Also, such malfunction may occur due to variation in a terminal power supply or external electromagnetic interference.
Besides, there is no guarantee of security for this kind of solution. As long as a phone call comes in or a short message is received, power-on and wakeup signals are generated regardless of the authenticity of the incoming signals and without any essential security verification on these signals.
As a result, the technical problem to be solved is how to provide an accurate and secured WAN module based remote wakeup system and terminal.